Switching on headlights stops the electric windows from working.

[ABliss]

I've been having some CCM issues recently but never knew what was causing it. I looked under the carpet and it was dry. The plenum chamber was cleared out and wasn't blocked that badly.

After some fault finding, I noticed that during the day the electric windows and the remote locking would work flawlessly. But, at night when I switch on the headlights my electric windows don't work and I have to wait about 10 minutes before I can remotely lock the car after parking up. Any ideas on what I should be looking for?

I had a thought that it could be something to do with an earth wire maybe or the current draw from the headlights causing some issue. Do you think a cold should be carried out (disconnecting negative and positive on battery and then shorting them together)?

[ABliss]

Any help? Just looking for the relationship between the headlight switch and the electric windows and remote locking.

[ADCS]

I can't really help but I can pose a few questions to maybe get you on the right path...

How much history do you have on the car?
Has there been any major electrical repairs that you know of?
Factory headlights? Xenon? Halogen? HID retrofit?
Original CCM and CECM?
What year is your car?
1.8t? 3.0? 1.9tdi?
Do you have VCDS? Have you scanned for module errors? Checked measuring blocks before and while it is acting up?

[ABliss]

I can't really help but I can pose a few questions to maybe get you on the right path...

How much history do you have on the car?
Has there been any major electrical repairs that you know of?
Factory headlights? Xenon? Halogen? HID retrofit?
Original CCM and CECM?
What year is your car?
1.8t? 3.0? 1.9tdi?
Do you have VCDS? Have you scanned for module errors? Checked measuring blocks before and while it is acting up?

Cheers ADCS. I'll Have a look at my scans from VCDS and work my way through the list. It's the starting point I needed. Thanks again.

What year is your car? 2001
1.8t? 3.0? 1.9tdi? 2.0 petrol sport.

Scans: These were commenced while car was on idle and everything working OK (windows worked and headlights off)

Address 09: Cent. Elect. Labels: 8E0-907-279-8E2.lbl
Part No: 8E0 907 279
Component: int. Lastmodul RDW 0510
Coding: 00001
Shop #: WSC 63351
VCID: 6FF5C587E79DFC4AF63A1D1-4B1A

1 Fault Found:
01330 - Central Control Module for Central Convenience (J393)
49-10 - No Communications - Intermittent



Address 17: Instruments Labels: 8E0-920-9xx-8E2.lbl
Part No: 8E0 920 950 D
Component: KOMBI+WEGFAHRS. RB4 D10
Coding: 00400
Shop #: WSC 00001
VCID: 2A4314931CFFD96261C404D-515E
WAUZZZ8EZ1A024866 AUZ6Z0A0010728

3 Faults Found:
01330 - Central Control Module for Central Convenience (J393)
49-10 - No Communications - Intermittent
01334 - Door Control Module; Rear Right (J389)
49-10 - No Communications - Intermittent
01333 - Door Control Module; Rear Left (J388)
49-10 - No Communications - Intermittent




Address 46: Central Conv. Labels: 8E0-959-433-MIN.lbl
Part No: 8E0 959 433 AC
Component: Komfortgerát T9F 0313
Coding: 06858
Shop #: WSC 63351
VCID: 72F3CCF3F4AFD1A219143CD-4B00

Subsystem 1 - Part No: 8E2959802B
Component: Tõrsteuer.FS BRM 4.11

Subsystem 2 - Part No: 8E2959801B
Component: Tõrsteuer.BF BRM 4.11

3 Faults Found:
01616 - Signal Wire to Interior Monitor
49-00 - No Communications
01702 - Footwell Lighting; Left (W9)
29-00 - Short to Ground
01697 - Footwell Lighting; Rear Right (W46)
29-00 - Short to Ground




I will be looking further into this. But, if anyone has any idea what these mean please feel free to contribute.

[diagnosticator]

Any help? Just looking for the relationship between the headlight switch and the electric windows and remote locking.

There is no relationship between the electric windows and the headlights.. The remote locking operates via the comfort module and the door control modules.

I don't know how it could be possible for the windows and locks to malfunction when the headlights are on, then work properly when the headlights are off.

Does your A4 have highline or lowline electrical system? Highline powers and controls the headlights via the Central Electric control module, there is no power supply from the fuse panel. Lowline powers the headlights from fuses in the fuse panel.

01330 There is a fault in the CAN bus between the CECM and the CCM.

Does your A4 have power or manual rear windows?